Full Report
View CSAF 1. EXECUTIVE SUMMARY CVSS v4 8.5 ATTENTION: Low attack complexity Vendor: Delta Electronics Equipment: CNCSoft-G2 Vulnerability: Heap-based Buffer Overflow 2. RISK EVALUATION Successful exploitation of this vulnerability could allow an attacker to execute code remotely. 3. TECHNICAL DETAILS 3.1 AFFECTED PRODUCTS Delta Electronics reports that the following versions of CNCSoft-G2, a human-machine interface, are affected: CNCSoft-G2: Versions V2.1.0.10 and prior 3.2 VULNERABILITY OVERVIEW 3.2.1 HEAP-BASED BUFFER OVERFLOW CWE-122 Delta Electronics CNCSoft-G2 lacks proper validation of the length of user-supplied data prior to copying it to a fixed-length heap-based buffer. An attacker can manipulate users to visit a malicious page or file to leverage this vulnerability to execute code in the context of the current process. CVE-2025-22881 has been assigned to this vulnerability. A CVSS v3.1 base score of 7.8 has been calculated; the CVSS vector string is (CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H). A CVSS v4 score has also been calculated for CVE-2025-22881. A base score of 8.5 has been calculated; the CVSS vector string is (CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N). 3.3 BACKGROUND CRITICAL INFRASTRUCTURE SECTORS: Energy, Critical Manufacturing COUNTRIES/AREAS DEPLOYED: Worldwide COMPANY HEADQUARTERS LOCATION: Taiwan 3.4 RESEARCHER Trend Micro Zero Day Initiative reported this vulnerability to CISA. 4. MITIGATIONS Delta Electronics recommends users update to CNCSoft-G2 v2.1.0.20 or later. Delta Electronics published a product cybersecurity advisory (Delta-PCSA-2025-00003) for this issue. For more information, please contact Delta Electronics Customer Service. Delta Electronics recommends the following general cybersecurity practices: Don't click on untrusted Internet links or open unsolicited attachments in emails. Avoid exposing control systems and equipment to the Internet. Place systems and devices behind a firewall and isolate them from the business network. When remote access is required, use a secure access method, such as a virtual private network (VPN). CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies. Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time. This vulnerability is not exploitable remotely. 5. UPDATE HISTORY March 4, 2025: Initial Publication
Analysis Summary
# Vulnerability: Delta Electronics CNCSoft-G2 Heap-based Buffer Overflow
## CVE Details
- CVE ID: CVE-2025-22881
- CVSS Score: 8.5 (High) (CVSS v4.0) / 7.8 (High) (CVSS v3.1)
- CWE: Heap-based Buffer Overflow (Implicit)
## Affected Systems
- Products: Delta Electronics CNCSoft-G2 (Human-Machine Interface)
- Versions: V2.1.0.10 and prior
- Configurations: Not specified, exploit requires user interaction (visiting a malicious page/file).
## Vulnerability Description
The vulnerability is a Heap-based Buffer Overflow due to Delta Electronics CNCSoft-G2 failing to properly validate the length of user-supplied data before copying it to a fixed-length heap buffer. An attacker can leverage this by manipulating a user to open a malicious file or visit a malicious webpage, leading to remote code execution within the context of the affected process.
## Exploitation
- Status: No known public exploitation reported to CISA at this time.
- Complexity: Low (Based on the CISA summary noting "Low attack complexity" in CVSS v4 context).
- Attack Vector: Local (Requires user interaction via file/page access - UI:P in CVSS vector, AV:L in CVSS vectors). Cannot be exploited remotely without user interaction.
## Impact
- Confidentiality: High (C:H in both vectors)
- Integrity: High (I:H in both vectors)
- Availability: High (A:H in both vectors)
## Remediation
### Patches
- Update to CNCSoft-G2 **v2.1.0.20 or later**.
### Workarounds
- Do not click on untrusted Internet links or open unsolicited attachments in emails.
- Avoid exposing control systems and equipment to the Internet.
- Place systems and devices behind a firewall and isolate them from the business network.
- Use a secure access method, such as a virtual private network (VPN), for required remote access.
## Detection
- Indicators of Compromise (IOCs): Not explicitly listed, but look for abnormal process behavior immediately following user interaction with external/untrusted content within the scope of the device or host running the HMI software.
- Detection methods and tools: Implement general cybersecurity monitoring and segmentation for ICS assets. Organizations should follow established internal procedures and report suspected malicious activity to CISA.
## References
- Vendor advisory: hxxps://filecenter.deltaww.com/news/download/doc/Delta-PCSA-2025-00003\_CNCSoft-G2%20-%20Heap-based%20Buffer%20Overflow\_v1.pdf
- CISA ICS General Guidance: hxxps://www.cisa.gov/topics/industrial-control-systems
- ICS Defense-in-Depth: hxxps://us-cert.cisa.gov/sites/default/files/recommended_practices/NCCIC\_ICS-CERT\_Defense\_in\_Depth\_2016\_S508C.pdf
- ICS Proactive Defense Best Practices: hxxps://www.cisa.gov/sites/default/files/publications/Cybersecurity\_Best\_Practices\_for\_Industrial\_Control\_Systems.pdf
- ICS Targeted Intrusion Detection: hxxps://www.cisa.gov/uscert/ics/tips/ICS-TIP-12-146-01B